Physiology of the Secretion of Acid, Pepsin, Sulfated Polysaccharides and Glycoproteins by the Dog Fundic Mucosa

Abstract

The secretion of acid, pepsin, chondroitin sulfate and glycoproteins from mucus have been studied in four Heidenhain pouch dogs, under basal condition and during stimulation with histamine, a gastrin- like pentapeptide and a cholinergic drug. Histamine and the gastrin analogue stimulate acid and, to a lesser extent, pepsin secretion, and they inhibit mucus secretion; cholinergic stimulation increases the output of acid, chondroitin sulfate, pepsin and glycoproteins of the mucus. No qualitative changes in the secretion of peptic or mucous cells are observed.

Effects of Cortisone on Acid, Pepsin, Sulfated Polysaccharides and Glycoprotein Secretion by the Mucosa of Denervated Fundic Pouches of Dogs

“…Thus, this secretion was primarely stimulated by the gastrointestinal hormones. Previous studies have shown that the mucous secretion was poorly stimulated or even inhibited in these circomstances [13], Conversely, the combined histaminic and cholinergic stimulation used in our study stimulates the mucous secretion. Thus, this latter study explores the capacity of mucous cells to secrete glycoproteins, while G oksen and Hardy study refers to the secretion in response to a hormonal stimulation.…”

“…The latter constitute the visible mucus, and only a small fraction of this visible mucus dissolves in the gastric juice [5], Under fasting conditions, mucous cells of the surface secrete continuously their glycoproteins but the acid, pepsin and chondro'ftin sulfate outputs are low. Stimulation by hista mine or gastrin increases acid but decreases mucus secretion, while during a combined stimulation by gastrin and a vagoniimetic, or histamine and a vagomimetic, peptic, parietal and mucous cells were all strongly stimulated [13]. Thus, such a combined stimulation was used to study the effects of corticosteroids on the activity of the different cells of the fundic mucosa.…”

“…The visible mucus was separated by centri fugation and the following determinations were made: ( I ) volumes of samples; (2) concen tration of acid by titration with 0.1 N NaOH, using phenol red as indicator; (3) pepsin by the method of Anson and M irsky modified by G lass et at. [10]; (4) chondro'itin sulfate by the method of De G raef and G lass [6]; (5) total glycoproteins of the visible mucus either by the estimation of the total hexosamine content of the visible mucus without fractionation, using the method of Rimington [17] or by determination of neutral hexoses with the anthronc method after digestion of the mucus by a mixture of papain and testicular hyaluronidase [13); (6) acidic glycoproteins of the visible mucus by the anthronc assay for neutral hexoses, after digestion of the mucus with papain and testicular hyaluronidase followed by CPC precipitation [13]. In some experiments, the 30-minute samples were pooled and the assays were performed on this pool representing the total collection of a 3-hours stimulation.…”

“…Isolation, chemical characterization and determination of cellular derivation of sulfated polysaccharides and glycoproteins from the fundic secretion in dogs allowed a detailed study of the physiology of peptic and mucous cells of the fundus [5][6][7]13]. In the present study, similar techniques were applied to study the effects of acute and chronic administration of corticoi'ds on dog fundic secretion.…”

Composition of Gastric Mucinous Secretion from Heidenhain Pouches of Dogs Treated with Aspirin

“…Ley et al (34) reported that gastrin-like pentapeptide induced 'a drop of the output of both total and acidic glycoproteins of the mucus', during the first hour of gastrin-like stimulation of canine stomachs. Thus, the difference between fasting and pentagastrin-stimulated gastric 'control' collections, regarding gastric mucus, can be explained by the 'acute' action of pentagastrin.…”